Purpose
This study aimed to determine the eye movement parameter(s) that is primarily affected when fully sighted subjects use plus-lens
magnifiers for
reading.
Methods
Two forms of plus-lens magnifier were used: hand-held and spectacle-mounted.
Eye movements were recorded using an infrared limbal reflection system as subjects read passages of text with and without the
magnifiers. Data were compared for a young
age group and an elderly (education-matched)
age group.
Results
For both
age groups, a sawtooth pattern of
eye movements was observed and
reading speed was significantly (p = 0.0001) reduced when using the
magnifiers compared with
reading without. Forward saccade length decreased significantly (p = 0.0001) and time for retrace increased significantly (p = 0.0001), but fixation durations were unaffected. The form of magnifier had no significant effect on
reading speed or eye movement parameters.
Conclusions
The reduction in
reading speed that occurred when using the plus-lens
magnifiers was primarily a result of decreased forward saccade length.
